This application is related to co-pending patent application Ser. No. 08/494,118, filed Jun. 23, 1995, entitled "Aircraft Landing Determination Apparatus and Method," which is incorporated herein by reference and which is assigned to the same assignee hereof.
1. Field of the Invention
The invention herein regards air traffic control systems, and particularly to air traffic control systems integrating airborne and ground-based target tracking and providing an integrated hazard response.
2. Description of the Prior Art
Accidents involving aircraft and ground vehicles and aircraft ground collisions can occur at busy airports. More than three times as many near-accidents occur on the ground as in the air. In one such accident, an aircraft strayed onto the wrong runway and was struck by a second aircraft, resulting in a loss of life. In another accident, two aircraft collided when one aircraft was cleared to land on an occupied runway. Continuous situation monitoring in fog, snow, at night, and under other adverse conditions, can cause fatigue in human controllers which may lead to a collision between objects on airport surfaces.
Medium-range airport surveillance radar, such as the Automated Radar Terminal System (ARTS) is good for detecting and tracking many aircraft within a large volume of airspace. However, such systems do not provide adequate surveillance coverage for ground-resident objects, including aircraft that are in the taxiing, holding (stopped), takeoff or landing phases of their flight profiles.
Airport surface detection equipment (ASDE) systems can provide high-resolution, short-range, clutter-free, surveillance information on aircraft and ground vehicles, both moving and fixed, located on or near the surface of airport movement and holding areas under all weather and visibility conditions. An ASDE system formats incoming surface detection radar information for a desired coverage area, and presents it to local and ground controllers on high-resolution, bright displays in the airport control tower cab.
However, an ASDE system will be effective only if the controllers are observing the radar display, which may be unlikely during good visibility conditions. The increasing sophistication of electronic equipment in air traffic control towers can result in an increasing number of computer displays and alarms. The large number of displays and keyboards in the tower cab can result in a cramped and cluttered environment which may be relieved by an integrated display apparatus. In addition to ASDE and ARTS systems, other sensor systems such as, for example, secondary surveillance radar (SSR), and global positioning system (GPS) can provide logically disparate parameters in physically disparate locations within the tower cab, further adding to the controllers' burden. The lack of integration between sensor systems in the tower cab, including ARTS, ASDE, SSR, GPS, and the like, can yield gaps in controller awareness of the unfolding situation.
In addition, a large, busy airport is an environment having a vast number of possible conflict situations. In such a dynamic environment, the potential for collision between any given aircraft and any one of possibly many ground-resident, and nearby airborne, objects may not be recognized until it is too late to avoid the collision. Also, the occurrence of a conflict in one area of the airport may draw controllers' attention away from evolving conflict situations.
What is needed is apparatus which can integrate inputs from disparate sensor systems to aid controllers in adverse conditions, such as poor visibility conditions or peak traffic periods, and provide an improved means of detecting and alerting the controller to pending surface conflict.